Chlorophoxes did not always exist in this world.
Originally, there was a reasonably sized colony of foxes that lived in a valley near New Brookfield. However, as the city grew, their water needs expanded; eventually a dam was built downriver of the city, with hydroelectric generators and water processing equipment. The contractors didn't pay too much mind to the surrounding nature area, though... and with the building of the dam, a small river than ran through the valley suddenly began to swell in size.
The walls of the valley were too steep and slick for most of the foxes to escape the rising waters; a few made it out, but many more slipped and fell back down, sometimes suffering injury or death. The foxes who did not wish to risk climbing the slippery walls fled to the trees, forming nests inside the branches of larger plants, and building nests on external branches.
Water soon engulfed the entire bottom of the valley, leaving only treetops exposed. The foxes adapted, however, slowly forming wider paws with longer claws that aided in tree-climbing and fish catching; with the ground entirely gone, fish and the occasional bird were the only food available.
However, the dam wasn't the only problem the humans presented to the foxes. The water was filtered going in to the city, yes... but the water that was let through the dam was often tainted with one thing or another, or debris-filled; and the large number of trees in the valley played very well at catching all of these things. The foxes managed alright, having larger and more developed bodily systems better able to process such things, but the fish mostly died out from contamination... leaving the foxes with little to no food.
At this point its a tad unclear what happened... somehow, maybe through high exposure to the plant-life around them and the lack of edible food, they began to take on characteristics of the trees they made their homes in. Many, many foxes did not make it; but sometimes, one would be born with thinner hairs and an instant craving for sunshine. The foxes slowly began to take heavily to sunbathing, and began to swim more, finding their wider paws very useful for such.
Eventually the foxes evolved out of their need for physical food; so long as they had plenty of sunshine to bask in, and plenty of water to drink and play in, they stayed healthy and happy. Their pelts sported thinner hairs, that allowed sunshine to reach their skin more easily; they were able to use the sunlight to produce energy, just like a plant. And while swimming, nutrients were absorbed through their pawpads in small amounts, just enough to supplement their intake from drinking.
Its not entirely known how the foxes could have changed so much in such a comparatively short amount of time; evolution usually takes place over thousands of years, while the foxes managed to become as they were in a manner of years. Maybe it was something contaminating the water that they ingested, or something filling the air from the factories in New Brookfield. Either way, it was a marvelous display of adaptability.
